Isosorbide (or 1,4:3,6-dianhydrosorbitol, see formula below) is the anhydride of sorbitol.

Upon heating sorbitol with an acid, for example concentrated sulfuric or hydrochloric acid, two molecules of water are eliminated with the formation of isosorbide. These compounds are also known generally as dianhydrohexitols (including besides isosorbide, the isomers isomannide and isoidide). Besides isosorbide, certain derivatives of isosorbide are well known, inter alia mono- and diesters, and ethers, in particular, mono- and dimethylethers of isosorbide. Those ethers are known to have good solvent properties for pharmaceutical and cosmetic compositions. EP 186 276 A2 discloses C1-C4 alkyldiethers of isosorbide, useful in oral hygiene preparations. The document discloses both symmetrical as well as unsymmetrical ethers. A process for the preparation of such ethers is disclosed in EP 315 334 A2, using dialkylcarbonates and a basic catalyst to etherify the isosorbide. Chatti et al. reported in Recent Res. Devel. Organic Chem., 7 (2003): 13-20 ISBN: 81-7895-093-6, a method to prepare various dialkylethers of isosorbide using microwave irradiation. Simple isosorbide ethers are also known to be suitable in personal care applications, as disclosed in EP 1 216 685 A2.
Since isosorbide is derived from natural sources, by the double dehydration of starch, it is an interesting way to obtain new compounds based on renewable resources. In the fields of cosmetics, pharmaceuticals and home products, there is a continuing search for new derivatives with new properties to meet the needs of the application areas.